Motor vehicles contain numerous lighting devices for both interior and exterior illumination. For example, exterior vehicle lighting devices may perform stop lamp functions, tail lamp functions, headlamp functions, daytime running light functions, dynamic bending light functions, and fog lamp functions. Numerous studies have found that nighttime visibility is a key to highway safety.
In an effort to improve vehicle and pedestrian safety, most governments promulgate some form of safety regulations that specify motor vehicle lighting performance requirements. This helps to ensure adequate illumination of the roadway and enhance the visibility of motor vehicles on the roads so that their presence is perceived and their signals are understood in daylight, in darkness, and in conditions of reduced visibility.
It is prudent for vehicle manufacturers to design vehicle lighting devices which meet the technical requirements of various standards around the world and in particular, in their associated marketing regions. In recent years, vehicle lighting has also become important for its aesthetic appeal to consumers. Thus, vehicle manufacturers have made an effort to design vehicle lighting devices in consideration of the styling of the vehicle on which the lighting devices are mounted. Further, vehicle manufacturers can provide optional lighting effects (in addition to the required lighting functionality) to enhance a vehicle's illumination performance and styling.
It may be technically challenging to provide aesthetically appealing vehicle lighting devices while also meeting the necessary cost, technology, and regulatory requirements. For example, headlamps on currently manufactured cars and trucks typically use significant power and require various additional components, such as reflectors, lenses, cut-off devices, and the like. Aesthetic lighting effects lead to an even greater number of components and complexity. Such vehicle lighting devices often are not easily adapted to the styling of the vehicle.
In recent years, a number of vehicle manufacturers have begun using lamps having light-emitting diodes (LEDs). LED-source lamps help to meet desired lighting performance, reduce power, and provide improved aesthetic characteristics.
Headlamps having one or more laser diode light sources have also been used. A laser diode light source provides a high luminance source that is beneficial for down the road and in hot spot regions. However, headlamps having laser diode light sources are more costly than headlamps having LED light sources.
The “background” description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description which may not otherwise qualify as conventional art at the time of filing, are neither expressly nor impliedly admitted as conventional art against the present disclosure.